Conveyor chain

ABSTRACT

A conveyor chain is assembled from links comprising in an alternate arrangement blocks and pairs of left-hand side and right-hand side block links. Each pair of block links is with its end portions on either side connected by a transverse pin to the end portion of the adjacent block. According to the invention the middle portion of the block links is bent in an inward direction, i.e., in the direction of the opposite block link so that the space between the block links is narrowed to an extent which prevents the tow pin of a vehicle to be moved from engaging the chain between the blocks.

United States Patent 1 1 Fromme Oct. 29, 1974 [5 CONVEYOR CHAIN 3,389,662 6/1968 Jacoby 104 172 c Inventor Hans-Georg Fromme 15 3,590,744 7/1971 Galloway et al. lO4/l72 C gz gggy wetzlar Primary ExaminerM. Henson Wood, Jr. Assistant Examiner-Robert Saifer [22] Filed: Nov. 6, 1972 Attorney, Agent, or Firm-Krafft & Wells [21] Appl. No.: 303,829

[57] ABSTRACT [30] F i A li ti P i it D t convigyor chain is assemblesl frim lirziks c omptrising N 30, 1971 G .1 21 24 a lemme arrangement 5 Palm 0 0v ermany 59 5 hand side and right-hand side block links. Each pair of [52] CL 104/172 C 59/85 7 4 /250 C block links is with its end portions on either side con- 51 1m. (:1. ..B65g1 7/38 El6g 13/12 acted by a transverse Pin to the end Ponio of the [58 Field of Search 104 172 0 172 BT' adjacent l the n enti whs middle 19 1 2 4 91 pOI'tiOIl Of the blOCk links is bent lIl an inward dil'6C- & tion, i.e., in the direction of the opposite block link so that the space between the block links is narrowed to 56] References Cited an extent which prevents the tow pin of a vehicle to be UNITED STATES PATENTS Soll l98/l89 ll/l958 moved from engaging the chain between the blocks.

2 Claims, 4 Drawing Figures CONVEYOR CHAIN BACKGROUND OF THE INVENTION The invention relates to chains of a conveyor system mounted beneath the supporting surface of the vehicles to be moved. More particularly the invention relates to chains which comprise in an alternate arrangement solid central blocks and pairs of block links. By means of transverse pins the blocks and the block links are pivotably interconnected.

If a chain of such type is used in an undersurface conveyor system care has to be taken that the tow pins of the vehicles slide on the chain with the least possible friction and rattling which may cause increased wear both of the pin and of the chain. Further, it must be ensured that the tow pin does not engage the chain in the space between the block links but only at the dog sections provided for that purpose at preestablished intervals on the chain.

For this reason the block links have already been designed as one piece of u-shaped cross section in order to achieve an almost flat continuous upper surface of the chain. The same result will be obtained if the block links are provided with a bent-over portion along their upper edges which portions are wide enough as to almost contact one another along a middle line of the chain. Further, to the same end flat plates have already been inserted between the upper edges of the block links.

Chains of this type are, for example, disclosed in the U.S. Pat. No. 3,389,662 issued June 25, 1968 to Charles E. Jacoby. These chains have, however, a number of disadvantages. First, when the conveyor is constructed the chain is usually transported in parts to the place and is assembled on the spot. It is therefore essential that the parts can be packed to not too big, easy to handle packages. This cannot be done with block links of u-shaped cross section and it can also not be done with block links having bent-over portions as described above. Secondly, the prior art block links cannot be manufactured in one single operation. It is however, important that this can be done in order to keep the production costs as low as possible. Further, the block links on the left-hand side and on the right-hand side should be of identical shape so that they can be assem- -bled symmetrically in pairs.

It is, therefore, an object of the invention to provide a conveyor chain comprising block links which in a simple manner prevent the tow pins from engaging the chain at undesired places between the dog sections. It is a further object to provide block links of this type which may be manufactured at comparatively low costs; and another object of the invention is to provide block links which can be packed to small packages for easy transportation.

SUMMARY OF THE INVENTION The above stated objects are attained by providing block links having central portions which are curved in lateral direction. All block links are of similar shape and they are mounted in pairs in a symmetrical arrangement with the convex side of the curvatures facing one another. The deepness of the curvature or bentin portion is such that the distance between the facing convex sides is smaller than the diameter of the tow pin. In a simple manner it is thereby ensured that the tow pins cannot engage the chain at an unpredictable place but only at the dog sections provided for this purpose.

On theother hand, since the block links are of similar shape they may readily be packed together with the convex side of a first block link fitting into the concave side of a second block link.

For heavy duty purposes and if production costs and easy transportation are less important the block links may be provided with bent-over edges in parallel to the chain axis.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will be more readily comprehended from the following description when taken in conjunction with the appending drawings, wherein:

FIG. 1 is a plan view of a conveyor chain comprising the invented block links in a first embodiment,

FIG. 2 is a plan view of a conveyor chain comprising the invented block links in a second embodiment,

FIG. 3 is a sectional view of a pair of block links out along line III-III in FIG. 2, and

FIG. 4 is a sectional view of the junction area between a block link and the adjacent block taken along the line IVIV of FIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawings, FIG. 1 shows a first and a second block link 1 having a body portion with a constant cross section and which are arranged in opposite order on either side of the blocks 8. The end portions 2 and 3 of the block links 1 are slightly bent in inward direction to a degree which corresponds to the height of the pin head 6 of the connection pin 5. Between these ends the ends of the respective blocks 8 are positioned. The connection between the block links and the blocks is established in conventional manner by means of the pins 5 which are inserted and secured in appropriate holes of the links and the blocks (FIG. 4).

Between the end portions 2 and 3 each block link is provided with a further bend 4 in inward direction, i.e. in the direction towards the opposite block link. These bends 4 are deep enough so that the tow pin 7 (shown in FIG. 1 in dotted lines in a sectional view) cannot fall into the space between the blocks 8 but slides on the upper surface of the block links 1.

In the embodiment shown in the FIGS. 2 through 4 the block links 11 are provided with bent-over portions 12 along their upper and lower edges and extending in parallel to the longitudinal axis of the chain. Block links of this type may be used for heavy duty chains. They may preferably be manufactured by die forging.

What is claimed is:

l. A conveyor chain for pushing vehicles to be moved by engaging tow pins having a given diameter on vehicles by means of dog sections on the chain, said chain comprising in an alternate arrangement blocks and pairs of identically shaped but symmetrically arranged block links connected with their end portions to the ad jacent blocks by transverse pins, wherein the improvement comprises block links with each of said block links having a body with a constant cross section, said body having bent-in central portions having a convex side which is arranged on the chain with said convex side of the bend extending in the direction of the oppothe block links are provided with bent-over portions along their upper and lower edges. said bent-over portions extending in parallel to the longitudinal axis of the chain. 

1. A conveyor chain for pushing vehicles to be moved by engaging tow pins having a given diameter on vehicles by means of dog sections on the chain, said chain comprising in an alternate arrangement blocks and pairs of identically shaped but symmetrically arranged block links connected with their end portions to the adjacent blocks by transverse pins, wherein the improvement comprises block links with each of said block links having a body with a constant cross section, said body having bent-in central portions having a convex side which is arranged on the chain with said convex side of the bend extending in the direction of the opposite block link, thus eliminating the space between each pair of block links to an extent less than said given diameter which prevents said pins of vehicles from engaging the chain between the blocks.
 2. A conveyor chain as claimed in claim 1, wherein the block links are provided with bent-over portions along their upper and lower edges, said bent-over portions extending in parallel to the longitudinal axis of the chain. 